<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>圆角</title>
</head>
<body>
<div class="one">圆角1</div>
<div class="two">圆角2</div>
<div class="three">圆角3</div>
<div class="four">圆角4</div>
<div class="five">圆角5</div>
<div class="six">圆角6</div>
<style>
    div{
        padding: 100px;
        text-align: center;
        background: red;
        margin-top: 100px;
    }
    .one{
      border-radius: 15px 50px 30px 5px;
    }
    .two{
        border-radius: 15px 50px 30px;
    }
    .three{
        border-radius: 30px 100px;
    }
    .four{
        border-radius: 50px/40px;
    }
    .five{
        border-radius: 15px/50px;
    }
    .six{
        border-radius: 50%;
    }
</style>
</body>
</html>